<template>
    <div class="upload-file">
        <el-upload
            multiple
            drag
            :action="uploadFileUrl"
            :before-upload="handleBeforeUpload"
            :file-list="fileList"
            :limit="limit"
            :on-error="handleUploadError"
            :on-exceed="handleExceed"
            :on-success="handleUploadSuccess"
            :show-file-list="false"
            :headers="headers"
            class="upload-file-uploader"
            ref="fileUpload"
        >
            <i class="el-icon-upload"></i>
            <!-- 上传按钮 -->
            <div class="el-upload__text">
                将文件拖到此处，或<em>点击上传</em>
            </div>
            <!-- 上传提示 -->
            <div class="el-upload__tip" slot="tip" v-if="showTip">
                请上传
                <template v-if="fileSize">
                    大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
                </template>
                <template v-if="fileType">
                    格式为
                    <b style="color: #f56c6c">{{ fileType.join('/') }}</b>
                </template>
                的文件
            </div>
        </el-upload>

        <!-- 文件列表 -->
        <transition-group
            class="upload-file-list el-upload-list el-upload-list--text"
            name="el-fade-in-linear"
            tag="ul"
        >
            <li
                :key="file.url"
                class="el-upload-list__item ele-upload-list__item-content"
                v-for="(file, index) in fileList"
            >
                <el-link
                    :href="`${file.url}`"
                    :underline="false"
                    target="_blank"
                >
                    <span class="el-icon-document">
                        {{ getFileName(file.name) }}
                    </span>
                </el-link>
                <div class="ele-upload-list__item-content-action">
                    <el-link
                        :underline="false"
                        @click="handleDelete(index)"
                        type="danger"
                        >删除</el-link
                    >
                </div>
            </li>
        </transition-group>
    </div>
</template>

<script>
import { getToken } from '@/utils/token'

export default {
    name: 'FileImport',
    props: {
        // 值
        value: [String, Object, Array],
        // 数量限制
        limit: {
            type: Number,
            default: 5
        },
        // 大小限制(MB)
        fileSize: {
            type: Number,
            default: 5
        },
        // 文件类型, 例如['png', 'jpg', 'jpeg']
        fileType: {
            type: Array,
            default: () => ['xls', 'xlsx']
        },
        // 是否显示提示
        isShowTip: {
            type: Boolean,
            default: true
        },
        // 上传类型 ()
        uploadType: {
            type: String,
            default: ''
        }
    },
    data() {
        return {
            number: 0,
            uploadList: [],
            baseUrl: process.env.VUE_APP_BASE_API,
            uploadFileUrl: process.env.VUE_APP_BASE_API + '/tool/file/upload', // 请求地址
            headers: { token: 'Bearer ' + getToken() }, // 设置上传的请求头部
            fileList: []
        }
    },
    watch: {
        value: {
            handler(val) {
                if (val) {
                    let temp = 1
                    // 首先将值转为数组
                    const list = Array.isArray(val)
                        ? val
                        : this.value.split(',')
                    // 然后将数组转为对象数组
                    this.fileList = list.map(item => {
                        if (typeof item === 'string') {
                            item = { name: item, url: item }
                        }
                        item.uid = item.uid || new Date().getTime() + temp++
                        return item
                    })
                } else {
                    this.fileList = []
                    return []
                }
            },
            deep: true,
            immediate: true
        },
        uploadType: {
            handler(val) {
                if (val && val !== '') {
                    this.uploadFileUrl = process.env.VUE_APP_BASE_HOST + val // 请求地址
                } else {
                    this.uploadFileUrl = process.env.VUE_APP_BASE_API + val
                }
                console.log('当前地址：' + this.uploadFileUrl)
            },
            deep: true,
            immediate: true
        }
    },
    computed: {
        // 是否显示提示
        showTip() {
            return this.isShowTip && (this.fileType || this.fileSize)
        }
    },
    methods: {
        // 上传前校检格式和大小
        handleBeforeUpload(file) {
            // 校检文件类型
            if (this.fileType) {
                let fileExtension = ''
                if (file.name.lastIndexOf('.') > -1) {
                    fileExtension = file.name.slice(
                        file.name.lastIndexOf('.') + 1
                    )
                }
                const isTypeOk = this.fileType.some(type => {
                    if (file.type.indexOf(type) > -1) return true
                    if (fileExtension && fileExtension.indexOf(type) > -1)
                        return true
                    return false
                })
                if (!isTypeOk) {
                    this.$modal.msgError(
                        `文件格式不正确, 请上传${this.fileType.join(
                            '/'
                        )}格式文件!`
                    )
                    return false
                }
            }
            // 校检文件大小
            if (this.fileSize) {
                const isLt = file.size / 1024 / 1024 < this.fileSize
                if (!isLt) {
                    this.$modal.msgError(
                        `上传文件大小不能超过 ${this.fileSize} MB!`
                    )
                    return false
                }
            }
            this.$modal.loading('正在上传文件，请稍候...')
            this.number++
            return true
        },
        // 文件个数超出
        handleExceed() {
            this.$modal.msgError(`上传文件数量不能超过 ${this.limit} 个!`)
        },
        // 上传失败
        handleUploadError() {
            this.$modal.msgError('上传图片失败，请重试')
            this.$modal.closeLoading()
        },
        // 上传成功回调
        handleUploadSuccess(res, file) {
            if (res.code === 0) {
                // edit by 芋道源码
                this.uploadList.push({ name: res.data, url: res.data })
                this.uploadedSuccessfully()
            } else {
                this.number--
                this.$modal.closeLoading()
                this.$modal.msgError(res.msg)
                this.$refs.fileUpload.handleRemove(file)
                this.uploadedSuccessfully()
            }
        },
        // 删除文件
        handleDelete(index) {
            this.fileList.splice(index, 1)
            this.$emit('UploadDel', this.listToString(this.fileList))
        },
        // 上传结束处理
        uploadedSuccessfully() {
            if (this.number > 0 && this.uploadList.length === this.number) {
                this.fileList = this.fileList.concat(this.uploadList)
                this.uploadList = []
                this.number = 0
                this.$emit('UploadEnd', this.listToString(this.fileList))
                this.$modal.closeLoading()
            }
        },
        // 获取文件名称
        getFileName(name) {
            if (name.lastIndexOf('/') > -1) {
                return name.slice(name.lastIndexOf('/') + 1)
            } else {
                return ''
            }
        },
        // 对象转成指定字符串分隔
        listToString(list, separator) {
            let strs = ''
            separator = separator || ','
            for (let i in list) {
                strs += list[i].url + separator
            }
            return strs != '' ? strs.substr(0, strs.length - 1) : ''
        }
    }
}
</script>

<style scoped lang="scss">
.upload-file-uploader {
    margin-bottom: 5px;
}
.upload-file-list .el-upload-list__item {
    position: relative;
    margin-bottom: 10px;
    border: 1px solid #e4e7ed;
    line-height: 2;
}
.upload-file-list .ele-upload-list__item-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: inherit;
}
.ele-upload-list__item-content-action .el-link {
    margin-right: 10px;
}
</style>
